PURPOSE: To eliminate the prior corrosion at the brazed fillet part of the title sheet by cladding an Al-Si brazing material having specific Fe contents and a core subjected to componential regulation by the addition of Ti, Zr and Cr and to homogenizing treatment.
CONSTITUTION: The brazing material of Al-Si, Al-Si-Mg, A-Si-Mg-Bi or the like having, by weight, ≤0.2% Fe contents is prepd. The Al alloy contg. 0.7W1.5% Mn, 0.1W0.7% Mg, ≤0.2% Cu and ≤0.2% Fe and furthermore contg. total 0.02W0.30% of one or more kinds among Ti, Zn and Cr and the balance consisting of Al with inevitable impurities is regulated to the core. The core is subjected to homogenizing treatment at ≤500°C. The core and the above brazing material are clad and rolled into the Al brazing sheet for a drawn cup heat exchanger.
TAKIGAWA ATSUSHI
TAKEMOTO MASAO
